OBJECTIVES This case study aimed to compare the physical and specific physical fitness characteristics of sprint canoe and canoe slalom athletes, thereby identifying discipline-specific physiological and biomechanical demands that can inform tailored training strategies.METHODS Eleven male canoeists (sprint canoe = 5, canoe slalom = 6) participated in a comprehensive physical assessment comprising physical fitness tests (grip and back strength, sit-up, push-up, standing long jump, balance, reaction time, sit-and-reach, and trunk extension), isokinetic trunk strength and power at 60°/s and 120°/s, a 30-s Wingate cycle-ergometer test, and cardiopulmonary exercise testing (CPET). Group differences were analyzed using independent t-tests.RESULTS Significant differences among groups were observed in physical fitness (right-hand grip strength, back strength, sit-ups, push-ups, reaction time, and sit-and-reach), specific physical fitness [isokinetic trunk strength: extensor (Nm, %BW) and flexor (Nm, %BW) at 60°/sec and 120°/sec; anaerobic power: peak power, peak power (W/kg), and average power (W/kg)], and cardiopulmonary fitness (maximal exercise time).CONCLUSIONS Sprint canoe athletes showed superior strength, trunk muscle function, and anaerobic power, whereas canoe slalom athletes tended to exhibit better balance and agility. Therefore, training should be tailored to the characteristics of each discipline, emphasizing power and strength development for sprint canoeists and focusing on core stabilization and agility improvement for slalom canoeists.

High-intensity or repetitive exercise induces metabolic stress and neuromuscular fatigue in skeletal muscle. Using a within-subjects repeated-measures crossover design, eight male amateur swimmers completed five experimental sessions at one-week intervals. Following an isokinetic fatigue protocol, five recovery interventions were applied in a randomized order: control (NT), foam roller (FR), vibration foam roller (VFR), and whole-body vibration at 12 Hz (WBV-12) and 20 Hz (WBV-20). The isokinetic fatigue protocol produced a significant reduction in bilateral extensor peak torque (229.2 ± 37.8%BW to 189.8 ± 27.5%BW; t(7) = 4.19, p = 0.004, d = 1.48), confirming successful fatigue induction. Outcome measures included visual analog scale (VAS) scores, blood lactate concentration, and knee extensor/flexor peak torque (%BW) assessed at three time points. A two-way repeated-measures ANOVA (intervention × time) revealed significant main effects of recovery methods at the post-recovery time point for VAS scores (F(4,28) = 5.98, p = 0.001, η²g = 0.248), blood lactate (F(4,28) = 5.12, p = 0.003, η²g = 0.226), and isokinetic peak torque (F(4,28) = 10.75, p < 0.001, η²g = 0.226). Post hoc Bonferroni analysis indicated that VFR and WBV-20 produced significantly higher lactate recovery rates than NT. Active recovery interventions produced lower perceived fatigue scores and greater lactate reductions than passive rest; however, individual Bonferroni pairwise comparisons for VAS and blood lactate did not reach adjusted significance, and these findings should be considered preliminary. WBV-20 demonstrated statistically confirmed superiority in isokinetic muscle function recovery (Bonferroni p < 0.05 vs. NT, FR, and VFR), suggesting its potential as an effective post-exercise recovery strategy for neuromuscular restoration.

During the competitive season, athletes often experience declines in neuromuscular performance due to the inconsistent implementation of maximal strength training. Although maximal strength training enhances athletic performance, its efficacy during the competitive season remains unclear, particularly in adolescent wrestlers. Therefore, this study investigated the effects of in-season maximal strength training on the physical fitness and neuromuscular performance of adolescent wrestlers. Thirty adolescent wrestlers were randomly assigned to either the maximal strength training group (MSTG) or control group (CG). Following five withdrawals, 25 participants (MSTG, n = 12; CG, n = 13) completed the study and were included in the final analysis. The MSTG performed a 50-min maximal strength training program once per week during the competitive season, while the CG maintained their regular training routine. Physical fitness variables (back strength, muscular endurance, power, agility, reaction time, and coordination) and neuromuscular performance (anaerobic power and isokinetic lumbar strength) were assessed pre- and post-intervention. Data were analyzed using a two-way repeated-measures analysis of variance (ANOVA). Significant group × time interaction effects were observed for back strength (p = 0.036), standing long jump (p = 0.016), side-step (p < 0.01), lumbar extensor strength at 60°/s (p = 0.037), and average power (p < 0.001). Lumbar extensor strength increased in the MSTG, whereas average power was maintained compared with a decline in the CG. No significant interaction effects were observed for the other variables. These findings suggest that competitive-season maximal strength training may improve selected physical fitness outcomes and help maintain selected neuromuscular performance outcomes in adolescent wrestlers.

High-intensity, repetitive exercise induces metabolic stress and neuromuscular fatigue in skeletal muscle. Muscle fatigue involves both peripheral and central mechanisms, impairing contractile function and increasing pain perception, thereby compromising athletic performance and elevating injury risk. Using a repeated-measures crossover design, eight male amateur swimmers completed five experimental sessions at one-week intervals. Following an isokinetic fatigue protocol, five recovery interventions were applied in randomized order: control, foam roller (FR), vibration foam roller (VFR), whole-body vibration at 12 Hz (WBV-12), and 20 Hz (WBV-20). Outcome measures included visual analogue scale (VAS) scores, blood lactate concentration, and knee extensor peak torque assessed at three time points. Significant main effects of recovery method were observed for VAS scores (F = 2.892, p = .036, η² = 0.248), blood lactate (F = 2.937, p = .034, η² = 0.251), and peak torque (p < .05). Active recovery interventions, particularly vibration-based modalities, were more effective than passive rest. WBV-20 demonstrated the most consistent recovery effects, suggesting its potential as an effective post-exercise recovery strategy.

OBJECTIVES This study examined the effects of an 8-week combined plyometric and change-of-direction (COD) repeated-shuttle-sprint training program on physical fitness, intermittent running performance, and blood lactate responses in female high school soccer players.METHODS Seventeen female high school soccer players (age, 17.1 ± 0.8 years) completed the program twice weekly for 8 weeks (16 sessions) in addition to their regular soccer training. Each session included a progressive plyometric block and a COD repeated-shuttle-sprint block, with sets terminated when performance declined by more than 5% relative to the first repetition. Muscular power and lower-extremity muscular endurance (repeated jump, standing long jump, and vertical jump), agility and reaction ability (side-step, light and sound reaction time), linear sprint performance (20, 40, and 200 m), and 30-15 Intermittent Fitness Test (30-15 IFT) performance were assessed before and after training. Blood lactate concentration was measured at rest and immediately, 3 min, and 5 min after the 30-15 IFT. Paired-samples t-tests or Wilcoxon signed-rank tests were applied according to normality, and effect sizes were calculated (p < 0.05).RESULTS Repeated jump performance increased by 19.2% (p < 0.001, dᶻ = 1.51), standing long jump by 2.4% (p = 0.045, dᶻ = 0.53), and vertical jump by 3.7% (p = 0.023, r = 0.55). Side-step performance increased by 10.2% (p = 0.007, dᶻ = 0.75), while light reaction time decreased by 7.4% (p = 0.029, dᶻ = 0.58). Sound reaction time did not change significantly (p = 0.132, dᶻ = 0.38). In the 30-15 IFT, the number of repetitions increased by 10.6% (p = 0.001, r = 0.84), total distance by 14.2% (p = 0.001, r = 0.81), and final running velocity by 6.1% (p = 0.001, r = 0.83). Estimated VO₂max increased by 1.2% (p = 0.010, r = 0.62), whereas maximal heart rate did not change significantly (p = 0.389, dᶻ = 0.21). Blood lactate concentration decreased by 48.8% at rest (p < 0.001, dᶻ = 1.37), 42.3% immediately post-exercise (p < 0.001, r = 0.88), 43.4% at 3 min post-exercise (p < 0.001, dᶻ = 4.47), and 28.8% at 5 min post-exercise (p < 0.001, dᶻ = 1.48). No significant changes were observed in 20-, 40-, or 200-m sprint performance (p > 0.05).CONCLUSIONS The combined plyometric and COD repeated-shuttle-sprint program improved repeated lower-extremity power, change-of-direction ability, and intermittent running performance in female high school soccer players. The largest fitness-related effect was observed for repeated jump performance, suggesting that the program may be particularly effective for enhancing the ability to repeatedly produce and maintain lower-extremity power. Blood lactate concentrations were lower after training despite greater intermittent running performance; however, the physiological mechanisms underlying these changes were not directly assessed. Light reaction time improved, whereas sound reaction time did not; however, because visual-cue tasks were included only during the final two weeks and changes in ligh

OBJECTIVES This case study aimed to compare the physical and specific physical fitness characteristics of sprint canoe and canoe slalom athletes, thereby identifying discipline-specific physiological and biomechanical demands that can inform tailored training strategies.METHODS Eleven male canoeists (sprint canoe = 5, canoe slalom = 6) participated in a comprehensive physical assessment comprising physical fitness tests (grip and back strength, sit-up, push-up, standing long jump, balance, reaction time, sit-and-reach, and trunk extension), isokinetic trunk strength and power at 60°/s and 120°/s, a 30-s Wingate cycle-ergometer test, and cardiopulmonary exercise testing (CPET). Group differences were analyzed using independent t-tests.RESULTS Significant differences among groups were observed in physical fitness (right-hand grip strength, back strength, sit-ups, push-ups, reaction time, and sit-and-reach), specific physical fitness [isokinetic trunk strength: extensor (Nm, %BW) and flexor (Nm, %BW) at 60°/sec and 120°/sec; anaerobic power: peak power, peak power (W/kg), and average power (W/kg)], and cardiopulmonary fitness (maximal exercise time).CONCLUSIONS Sprint canoe athletes showed superior strength, trunk muscle function, and anaerobic power, whereas canoe slalom athletes tended to exhibit better balance and agility. Therefore, training should be tailored to the characteristics of each discipline, emphasizing power and strength development for sprint canoeists and focusing on core stabilization and agility improvement for slalom canoeists.